JP6406097B2 - IDENTIFICATION INFORMATION SEARCH METHOD AND RADIO COMMUNICATION DEVICE - Google Patents

Description

  The technology disclosed in this specification relates to a method for retrieving identification information.

  In recent years, a wireless LAN (Local Area Network) has become widespread, and there are many access points such as a wireless LAN router and wireless communication devices having a wireless communication function. A wireless communication device having a wireless communication function such as a printer exchanges data with an external wireless communication device such as a PC or an external server via one access point selected from a plurality of access points. There are modes (infrastructure mode) and modes (ad hoc mode) for exchanging data with one external wireless communication device selected from a plurality of external wireless communication devices without going through an access point.

  In such a wireless communication device, for example, the user can connect to select one of a plurality of access points and a plurality of external wireless communication devices (hereinafter collectively referred to as “external communication devices”). The external communication device is searched, and identification information (for example, SSID (Service Set Identifier)) of the searched external communication devices is displayed on the display unit provided in the wireless communication device (see Patent Document 1). ).

  Here, in the external communication device, a communication channel used for wireless communication is predetermined for each device. Therefore, the wireless communication apparatus transmits a request signal in the communication channel for each communication channel, for example, a plurality of times at predetermined intervals. Each external communication device, when receiving the request signal, transmits a response signal including its own identification information to the wireless communication device. When the wireless communication device receives a response signal within a predetermined reception time, the wireless communication device can connect to the external communication device corresponding to the identification information from the identification information included in the response signal using the communication channel. Can be recognized.

JP 2010-74334 A

  However, conventionally, a wireless communication apparatus transmits a request signal multiple times at a predetermined interval for each communication channel under the same conditions for all communication channels, and the identification received within a predetermined reception time. Since the search processing for storing information is repeatedly executed, it takes time to search for identification information of all connectable external communication devices. For example, even when a sufficient number of identification information of connectable external communication devices can be received by executing a single search process for one communication channel because the communication environment is stable. As with other communication channels, the second and subsequent search processes are continued. For this reason, it takes time to search the identification information of all the connectable external communication devices by continuing the useless search process.

  Also, for example, when the communication environment is unstable, the search accuracy of the search process is low, or even when the search process is executed, a sufficient number of identification information of connectable external communication devices cannot be received There is. However, even in such a case, in the conventional wireless communication device, the search process of the same search condition is repeatedly executed, and thus there is a high possibility that the search for the identification information of the connectable external communication device will be missed.

  An object of the present invention is to search for identification information of external communication devices connectable to all communication channels at an early stage, for example, by quickly stopping the search for identification information received on a communication channel in which the communication environment is stable. By searching the identification information received on the communication channel where the environment is unstable by searching different conditions, it is possible to search faster than when searching with the same search condition for each communication channel. An object of the present invention is to provide an identification information search method and a wireless communication apparatus capable of suppressing information search omissions.

  The technology disclosed in this specification can be implemented as the following forms.

  The identification information search method disclosed in this specification searches for identification information of an external communication device using a wireless communication unit that transmits and receives data by designating an arbitrary communication channel from among a plurality of communication channels. A method for retrieving identification information, wherein a request signal for requesting identification information of an external communication device is transmitted to the wireless communication unit once, and the wireless communication unit is within a predetermined reception time from the time of transmission of the request signal. A first search step in which the unit search for acquiring the received identification information of the external communication device as an identification information group is performed twice for each communication channel, and the first identification acquired by the first unit search. A first determination step for determining, for each communication channel, whether or not the information group matches the second identification information group acquired by the second unit search, and among the plurality of communication channels, First A second search in which the unit search is performed under a condition different from that of the first search step for each unmatched channel determined that the first identification information group and the second identification information group do not match in the disconnection step And a process.

  The wireless communication apparatus includes a wireless communication unit that transmits and receives data by designating an arbitrary communication channel from among a plurality of communication channels, a control unit, a storage unit, and a display unit, and the control unit Transmits a request signal for requesting identification information of an external communication device to the wireless communication unit once, and the external communication device received by the wireless communication unit within a predetermined reception time from the time of transmission of the request signal. A unit search for storing identification information as an identification information group in the storage unit twice for each communication channel and a first search stored in the storage unit by the first unit search. A first determination process for determining, for each communication channel, whether or not the identification information group matches the second identification information group stored in the storage unit by the second unit search; Of the channels Included in the identification information group stored in the storage unit in the coincidence channel with respect to the coincidence channel determined to match the first identification information group and the second identification information group in one determination process The first display process for displaying the identification name of the identification information on the display unit, and among the plurality of communication channels, the first identification information group and the second identification information group match in the first determination process A second search process for performing the unit search under a condition different from that of the first search process for each unmatched channel determined not to be performed, and the unit search in the second search process after the first display process. And a second display process for displaying the identification name of the identification information included in the identification information group for each unmatched channel stored in the storage unit on the display unit.

  The technology disclosed by this specification can be implemented in various forms. For example, the present invention can be realized in the form of an identification information searching method and a wireless communication device, a computer program for realizing the function of the method or device, a non-temporary recording medium on which the computer program is recorded, and the like.

1 is a block diagram illustrating an electrical configuration of a printer 10 according to an embodiment. The figure which shows the printer 10, access point AP, and the external wireless apparatus W Flow chart showing control processing Flow chart showing SSID search processing Flow chart showing first search process Flow chart showing condition processing Flow chart showing second search process Flow chart showing time-up search processing Flow chart showing number-up search processing Flow chart showing transmission strength increase search processing Explanatory drawing which shows the relationship between the 1st SSID group of channel 1, and the 2nd SSID group Explanatory drawing which shows the relationship between the 1st SSID group of channel 5-the 3rd SSID group Explanatory drawing which shows the relationship between the 1st SSID group of channel 8-the 3rd SSID group The flowchart which shows the SSID search process of another embodiment

  One embodiment will be described with reference to FIGS.

  FIG. 1 is a block diagram showing an electrical configuration of the printer 10. 2 illustrates a printer 10, a plurality of access points AP (only AP1 to AP3 are shown in FIG. 2), and a plurality of external wireless devices W (only W1 to W3 are shown in FIG. 2). . The printer 10 is an example of a wireless communication device, and the access point AP and the external wireless device W are examples of an external communication device having a wireless communication function. The printer 10 includes a control unit 100, a wireless communication interface 200, a ROM 300, a RAM 400, an operation unit 500, a display unit 600, and a printing unit 700. The wireless communication interface 200 is an example of a wireless communication unit, and the RAM 400 is an example of a storage unit.

  The control unit 100 is configured by an ASIC (Application Specific Integrated Circuit) having a CPU 110. The ROM 300 stores a control program for controlling the printer 10, various settings, initial values, and the like. The RAM 400 is also used as a work area when the CPU 110 executes various programs and a temporary storage area for data. The CPU 110 controls each component of the printer 10 in accordance with a control program read from the ROM 300 and signals sent from various sensors whose illustration and detailed description are omitted.

  The wireless communication interface 200 has a wireless LAN antenna (not shown), for example, and designates an arbitrary communication channel from among a plurality of communication channels according to a command from the control unit 100 to exchange data with a specific external communication device. Is a device for performing exchange (transmission / reception). In the following description, the wireless communication interface 200 is provided with 13 communication channels assigned to a predetermined frequency band (for example, 2.4 GHz band), and the wireless communication interface 200 includes 13 communication channels. It is assumed that it is possible to exchange data (wireless communication) with an external communication device by designating any one communication channel from among them. Note that the communication standard of wireless communication adopted in the wireless communication interface 200 is, for example, IEEE802.11b, IEEE802.11a, IEEE802.11g, or the like.

  The wireless communication interface 200 is configured to execute switching between the infrastructure mode and the ad hoc mode. As shown in FIG. 2A, the wireless communication interface 200 executes one of the access points selected from a plurality of access points AP (only AP1 to AP3 are shown in the figure) by executing the infrastructure mode. Data can be exchanged with the personal computer P via the AP1. Also, as shown in FIG. 2B, the wireless communication interface 200 performs a plurality of external wireless devices W (only W1 to W3 are shown in the figure) without executing the access point AP by executing the ad hoc mode. It is possible to exchange data with one external external wireless device W1 selected from the above. Further, the wireless communication interface 200 can change the intensity of radio waves when performing wireless communication.

  The operation unit 500 includes various buttons that accept user operations. The display unit 600 is configured by a liquid crystal display, for example, and displays various types of information. The printing unit 700 forms an image on a sheet (not shown) using the image data received by the wireless communication interface 200 under the control of the CPU 110.

  When the printer 10 is turned on, the CPU 110 executes a control process shown in FIG. For example, the CPU 110 determines whether or not the operation unit 500 has received a search instruction within a predetermined time (S1). If the CPU 110 determines that the search instruction has been received (S1: YES), the CPU 110 executes the SSID search process shown in FIG. (S2). In the following description, the description is limited to the infrastructure mode, but the identification information of the connectable external wireless device W can be received by the same processing in the ad hoc mode.

  In the SSID search process, an access point AP that can be connected to the printer 10 is searched from an unspecified number of access points AP, and a connection destination candidate from which the user selects SSIDs of the searched access points AP. As shown in FIG. The SSID is an example of identification information of an external communication device. In the SSID search process, the CPU 110 first executes a first search process shown in FIG. 5 (S11).

  The first search process is a process of performing the unit search described below twice for each communication channel. The CPU 110 initializes the channel number N to zero (S101). The channel number N is assumed to be a consecutive number “1-13” assigned to each of the 13 communication channels described above. Next, the CPU 110 adds 1 to the channel number N (S102), and sets the mismatch flag M (N) to zero (off) (S103). Note that the fact that the mismatch flag M (N) is zero means that a first SSID group (N) and a second SSID group (N) described later match, and the mismatch flag M (N) is 1 or more. This means that the first SSID group (N) and the second SSID group (N) do not match.

  Next, the CPU 110 designates the Nth communication channel and performs a first unit search (S104 to S106). Specifically, the CPU 110 causes the wireless communication interface 200 to transmit a request signal (probe request) for requesting SSIDs of an unspecified number of external communication devices once with the first radio wave intensity (S104). Each access point AP transmits a response signal (probe response) to the request signal to the printer 10 if the connection with the printer 10 is possible. When the CPU 110 receives the response signal, the CPU 110 stores the SSID included in the response signal in the RAM 400 as the first SSID group (N) for the Nth communication channel (S105). The first SSID group (N) is an example of an identification information group.

  The CPU 110 determines whether or not a first reception time (for example, 50 μs) has elapsed since the transmission of the request signal (S106). When determining that the first reception time has not elapsed (S106: NO), the CPU 110 If it is determined that the first reception time has elapsed (S106: YES), the process of S105 is terminated. Here, the number of SSIDs stored as the first SSID group (N) in the process of S105 increases or decreases depending on the communication environment around the printer 10, the number of connectable external communication devices, and the like. There may be multiple, and even zero.

  Next, the CPU 110 designates the Nth communication channel and performs a second unit search (S107 to S109) under the same search conditions as the first unit search. Specifically, the CPU 110 causes the wireless communication interface 200 to transmit the request signal once with the first radio wave intensity (S107). When the CPU 110 receives a response signal corresponding to the request signal, the CPU 110 stores the SSID included in the response signal in the RAM 400 as the second SSID group (N) for the Nth communication channel (S108). The second SSID group (N) is an example of an identification information group.

  The CPU 110 determines whether or not the first reception time has elapsed since the transmission of the request signal (S109). If the CPU 110 determines that the first reception time has not elapsed (S109: NO), the processing of S108 is continued. If it is determined that the first reception time has elapsed (S109: YES), the process of S108 is terminated. Here, the number of SSIDs stored as the second SSID group (N) in the process of S108 also increases or decreases depending on the communication environment around the printer 10, the number of connectable external communication devices, and the like. There may be multiple, and even zero.

  After performing the second unit search, the CPU 110 matches all SSIDs included in the first SSID group (N) and all SSIDs included in the second SSID group (N) for the Nth communication channel. It is determined whether or not (S110). The process of S110 is an example of a first determination process. Note that the first SSID group (N) and the second SSID group (N) coincide with each other in that the number of SSIDs included in the first SSID group (N) and the number of SSIDs included in the second SSID group (N) Not included if both are zero.

  When the CPU 110 determines that the first SSID group (N) and the second SSID group (N) match (S110: YES), the SSID included in the first SSID group (N) is used as the SSID group (N) for display. It is stored in the RAM 400 (S111). At this time, since the first SSID group (N) and the second SSID group (N) match, in the process of S111, the CPU 110 converts the SSID included in the second SSID group (N) into the SSID group (N ) May be stored in the RAM 400. When the first SSID group (N) and the second SSID group (N) match (S110: YES), the Nth communication channel mismatch flag M (N) remains zero, and the Nth communication channel. Is an example of a matching channel.

  On the other hand, if the CPU 110 determines that the first SSID group (N) and the second SSID group (N) do not match (S110: NO), the CPU 110 executes the condition process shown in FIG. 6 for the Nth communication channel (S113). ). At this time, the Nth communication channel is an example of a mismatch channel. In the condition processing whose details are illustrated in FIG. 6, the CPU 110 determines the number of SSIDs at least one of the number of SSIDs included in the first SSID group (N) and the number of SSIDs included in the second SSID group (N) ( Hereinafter, it is determined whether or not the number of received SSIDs has reached the upper limit (S210). The process of S201 is an example of a second determination process. The upper limit number is the maximum number of SSIDs that the wireless communication interface 200 can receive within the unit search processing time, and is assumed to be five in the following description.

  Here, when the number of received SSIDs reaches the upper limit, the number of access points AP that cannot be received within the first reception time of the first search process (that is, six or more) for the Nth communication channel. Is determined to exist. Therefore, when the CPU 110 determines that the number of SSIDs received has reached the upper limit (S201: YES), the CPU 110 does not match the flag M (N) in order to execute a time-up search process (S305 in FIG. 7) described later. Is set to 1 (S202), this condition processing is terminated, and the process proceeds to S114 in FIG.

  When CPU 110 determines that neither the number of SSIDs included in the first SSID group (N) nor the number of SSIDs included in the second SSID group (N) has reached the upper limit number (S201: NO), The number of SSIDs included in one SSID group (N) and the number of SSIDs included in the second SSID group (N) (hereinafter, simply referred to as the number of SSIDs received) is zero. It is determined whether or not (S203). The process of S203 is an example of a third determination process. Here, when the number of received SSIDs is zero, there is a high possibility that the unit search in the first search process has not been executed normally due to temporary deterioration of the communication environment around the printer 10. Therefore, if the CPU 110 determines that the number of SSID searches is zero (S203: YES), the CPU 110 sets the mismatch flag M (N) to 2 in order to execute a number-up search process (S307 in FIG. 7) described later. Set (S204), this condition processing ends, and the process proceeds to S114 of FIG.

  When CPU 110 determines that neither the number of SSIDs included in the first SSID group (N) and the number of SSIDs included in the second SSID group (N) are non-zero, or both are zero (S203: NO), in order to execute a transmission strength increase search process (S308 in FIG. 7) to be described later, the mismatch flag M (N) is set to 3 (S205), this condition process is terminated, and the process proceeds to S114 in FIG. . In S114, the CPU 110 causes the RAM 400 to store the union of the SSID included in the first SSID group (N) and the SSID included in the second SSID group (N) as the SSID group (N). Thereby, in S12 described later, all SSIDs included in the first SSID group (N) and the second SSID group (N) are displayed on the display unit 600.

  After executing the process of S111 or S114, the CPU 110 determines whether or not the current channel number N has reached the total number of channels (S112). When the CPU 110 determines that the current channel number N has not reached the total number of channels (S112: NO), it means that there is a communication channel that has not been subjected to the unit search twice, so the process returns to S102, The first search process is performed for the communication channel of the next channel number N + 1. On the other hand, if the CPU 110 determines that the current channel number N has reached the total number of channels (S112: YES), it means that the unit search has been performed twice for all communication channels. The first search process is terminated, and the process proceeds to S12 in FIG.

  In S12 of FIG. 4, CPU 110 causes display unit 600 to display the SSID included in the SSID group (N) for each communication channel. The process of S12 is an example of a first display process. As a result, the SSIDs of the access points AP that can communicate with the printer 10 are displayed in a list on the display unit 600, so that the user can select an arbitrary SSID from the displayed SSID group. . The CPU 110 determines whether or not the operation unit 500 has received an SSID selection instruction from the user in a state where the SSID is displayed on the display unit 600 (S13).

  If the CPU 110 determines that an SSID selection instruction has been received (S13: YES), the CPU 110 establishes a communication connection with the access point AP of the SSID selected by the selection instruction without executing the second search process described below. Connection processing is performed (S14). Accordingly, the printer 10 can exchange data with the access point AP selected by the user through the wireless communication interface 200. CPU110 complete | finishes this SSID search process after execution of a connection process, and progresses to (S3) of FIG.

  When CPU 110 determines not to accept an SSID selection instruction (S13: NO), CPU 110 determines whether operation unit 500 has received an SSID re-search instruction from the user (S15). When the CPU 110 determines that the SSID re-search instruction has not been received (S15: NO), the CPU 110 returns to S13, and when it is determined that the SSID re-search instruction has been received (S15: YES), the second search illustrated in FIG. Processing is executed (S16).

  The second search process is a process of performing a unit search for each unmatched channel obtained in the first search process under conditions different from those in the first search process (in this embodiment, a condition with higher accuracy than the first search process). The CPU 110 initializes the channel number N to zero (S301). Next, the CPU 110 adds 1 to the channel number N (S302), and whether or not the mismatch flag M (N) of the Nth communication channel is zero, that is, the Nth communication channel is the above match channel. It is determined whether or not there is (S303). If the CPU 110 determines that the Nth communication channel is a coincidence channel (S303: YES), the CPU 110 proceeds to S309 without executing the following search processes (S305, S307, S308).

  If the CPU 110 determines that the Nth communication channel is not a coincidence channel, that is, the disagreement channel (S303: NO), whether or not the Nth communication channel mismatch flag M (N) is 1, That is, it is determined whether the number of received SSIDs of at least one of the first SSID group (N) and the second SSID group (N) has reached the upper limit number in the Nth communication channel (S304).

  When the CPU 110 determines that the number of received SSIDs of at least one of the first SSID group (N) and the second SSID group (N) has reached the upper limit number (S304: YES), the time-up search process shown in FIG. 8 is performed. Execute (S305). This time-up search process is a process for performing a unit search (S401 to S403) with a reception time longer than that of S106 and S109 of the first search process for mismatched channels whose SSID reception count has reached the upper limit. is there. Specifically, the CPU 110 causes the wireless communication interface 200 to transmit the request signal once with the first radio wave intensity (S401), and when the response signal is received, the SSID included in the response signal is changed to the Nth. The third SSID group (N) for the communication channel is stored in the RAM 400 (S402). The third SSID group (N) is an example of an identification information group.

  CPU 110 determines whether or not the second reception time has elapsed since the transmission of the request signal (S403). Here, the second reception time is a time (for example, 100 μs) longer than the first reception time of the first search process. For this reason, the upper limit number of SSIDs that can be received within the second reception time is also larger than that in the first search process. That is, in the second search process, a unit search is performed under conditions that are more accurate than the first search process. For this reason, it becomes possible to receive the number of SSIDs that could not be received in the first search process. Hereinafter, it is assumed that the upper limit number of SSIDs in the second reception time is ten. When CPU 110 determines that the second reception time has not elapsed (S403: NO), it continues the process of S402, and when it is determined that the second reception time has elapsed (S403: YES), this time up search The process ends, and the process proceeds to S309 in FIG.

  If the CPU 110 determines that the number of received SSIDs of the first SSID group (N) and the second SSID group (N) has not reached the upper limit number (S304: NO), the Nth communication channel mismatch flag M ( It is determined whether or not N) is 2, that is, whether or not the number of SSIDs received in the first SSID group (N) or the second SSID group (N) is zero in the Nth communication channel (S306). . When the CPU 110 determines that the number of SSIDs received in the first SSID group (N) or the second SSID group (N) is zero (S306: YES), the CPU 110 executes the number-up search process shown in FIG. 9 (S307). This number-up search process is a process in which the unit search is repeatedly performed on the non-matching channel in which the number of SSIDs received is zero, more times than the first search process, that is, three times or more.

  Specifically, the CPU 110 initializes the unit search repetition count L to zero (S501), adds 1 to the repetition count L (S502), and transmits the request signal to the wireless communication interface 200 once with the first radio wave intensity. When the response signal is received, the SSID included in the response signal is stored in the RAM 400 as the third SSID group (N) for the Nth communication channel (S504). Then, the CPU 110 determines whether or not the first reception time has elapsed since the transmission of the request signal (S505). If it is determined that the first reception time has not elapsed (S505: NO), the processing of S504 is performed. Continue. On the other hand, when CPU 110 determines that the first reception time has elapsed (S505: YES), CPU 110 determines whether or not the number of repetitions L has reached the specified number (S506). The specified number of times is 3 times or more, for example, 5 times.

  If the CPU 110 determines that the number of repetitions L has not reached the specified number (S506: NO), the CPU 110 returns to S502, and performs a unit search from S503 to S505 for the mismatched channel where the number of SSIDs received is zero. Repeat. On the other hand, if the CPU 110 determines that the number of repetitions L has reached the specified number (S506: YES), the CPU 110 ends the number-up search process and proceeds to S309 in FIG. As a result, the unit search is repeatedly performed more times than the first search process for the non-matching channel in which the number of SSIDs received is zero. That is, in the second search process, a unit search is performed under conditions that are more accurate than the first search process. For this reason, the execution of the number-of-times search process increases the possibility of receiving an SSID that has not been received due to a temporary deterioration of the communication environment in the first search process.

  If the CPU 110 determines that both the first SSID group (N) and the second SSID group (N) are not zero or both are zero (S306: NO), the CPU 110 executes the transmission strength increase search process shown in FIG. (S308). In this transmission strength increase search process, the strength of radio waves transmitted is stronger than S104 and S107 of the first search process for non-matching channels such as the number of received SSIDs not reaching the upper limit and non-zero. The unit search (S601 to S603) is performed. Specifically, the CPU 110 causes the wireless communication interface 200 to transmit the request signal once with the second radio wave intensity (S601), and when the response signal is received, the SSID included in the response signal is changed to the Nth. The third SSID group (N) for the communication channel is stored in the RAM 400 (S602).

  Here, the second radio wave intensity is higher than the first radio wave intensity of the first search process, and is an intensity capable of wireless communication over a wider distance. That is, in the second search process, a unit search is performed under conditions that are more accurate than the first search process. For this reason, it becomes possible to receive SSIDs of remote access points AP that could not be received in the first search process. The CPU 110 determines whether or not the first reception time has elapsed since the transmission of the request signal (S603). If it is determined that the first reception time has not elapsed (S603: NO), the processing of S602 is continued. If it is determined that the first reception time has elapsed (S603: YES), the transmission strength increase search process is terminated, and the process proceeds to S309 in FIG.

  In S309 of FIG. 7, the CPU 110 determines whether or not the current channel number N has reached the total number of channels, and determines that the current channel number N has not reached the total number of channels (S309: NO). Since this means that there is still an unprocessed communication channel, the process returns to S302, and determination processing such as S303 is performed for the communication channel of the next channel number N + 1. On the other hand, if the CPU 110 determines that the current channel number N has reached the total number of channels (S309: YES), it means that there is no unprocessed communication channel yet, so the second search process is terminated. The process proceeds to S17 in FIG.

  In S17 of FIG. 4, the CPU 110 determines whether or not there is a difference between the SSID included in the SSID group of all channels and the SSID included in the third SSID group of all channels, that is, in the second search process, the first search It is determined whether a new SSID that could not be received in the process has been received. When the CPU 110 determines that a new SSID has been received (S17: YES), the union of the SSID included in the SSID group (N) and the SSID included in the third SSID group (N) for each communication channel Is stored in the RAM 400 as the latest SSID group (N), and the process proceeds to S12. Thereby, in addition to the SSID received in the first search process, the SSID newly received in the second search process is displayed on the display unit 600. The process of S12 at this time is an example of a second display process.

  On the other hand, if the CPU 110 determines that a new SSID has not been received (S17: NO), it proceeds to S12 without executing the process of S18. For this reason, the SSID displayed on the display unit 600 is the same as at the end of the first search process.

  When the CPU 110 finishes the SSID search process, it determines whether or not the operation unit 500 has received a print command from the user (S3 in FIG. 3). If it is determined that the print command has been received (S3: YES), the SSID search process Print data is received via the access point AP selected in (S4), print processing is executed using the print data (S5), this control process is terminated, and after a predetermined time, again in FIG. The control process is started. Note that if the CPU 110 determines that the search instruction is not accepted in S1 (S1: NO), the CPU 110 does not execute the SSID search process, for example, while maintaining the connection state with the currently connected external communication device. Proceed to

  11A to 11C show the relationship between the first SSID group to the third SSID group for the first, fifth, and eighth channels. As shown in FIG. 11A, as a result of executing the first search process, the SSIDs of three access points I01 to I03 are included in the first SSID group (1) for the first communication channel, and the second SSID group Assume that (1) includes SSIDs of three access points I01 to I03. Thus, when the first SSID group (1) and the second SSID group (1) match, it is expected that the SSID of the connectable access point AP could be normally received in the first search process.

  Therefore, for the first communication channel, in S110 of FIG. 5, it is determined that the first SSID group (1) and the second SSID group (1) match (S110: YES), and I01 to I03 are displayed on the display unit 600. (S111, S12 in FIG. 4). Further, in S303 of FIG. 7, since it is determined that the first communication channel is a coincidence channel (S303: YES), the unit search for the first communication channel is not performed in the second search process. As a result, in the second search process, it is possible to prevent the unit search from being continued in vain as much as the matching channel is excluded.

  As shown in FIG. 11B, as a result of executing the first search process, the SSIDs of four access points I21 to I24 are included in the first SSID group (5) for the fifth communication channel. It is assumed that SSIDs of five access points I21 to I24 and I27 are included in the 2SSID group (5). Thus, when the first SSID group (5) and the second SSID group (5) are inconsistent and the first SSID group (5) has reached the upper limit number, the first search processing within the first reception time. Then, there is a high possibility that there are a number of access points AP that could not be received.

  Therefore, for the fifth communication channel, in S110 of FIG. 5, it is determined that the first SSID group (5) and the second SSID group (5) do not match (S110: NO), and in the condition processing of FIG. It is determined that the number of SSIDs received has reached the upper limit (S201: YES), and in the second search process of FIG. 7, a time-up search process (S305) is executed. As a result, as shown in FIG. 11B, I25, I26, and I28 are newly received and included in the third SSID group (5). As a result, it is possible to suppress the SSID search omission for mismatched channels in which there is a high possibility that there is an access point AP that is not searched in the first search process due to the length of the SSID reception time.

  As shown in FIG. 11C, as a result of executing the first search process, the SSID is not included in the first SSID group (8) for the eighth communication channel, and I31 is included in the second SSID group (8). It is assumed that SSIDs of three access points of ~ I33 are included. As described above, when one first SSID group (5) is zero and the other second SSID group (5) has not reached the upper limit, the unit search in the first search process is caused by the temporary deterioration of the communication environment. There is a high possibility that the SSID of the access point AP cannot be received sufficiently with the number of repetitions.

  Therefore, for the eighth communication channel, in S110 of FIG. 5, it is determined that the first SSID group (8) and the second SSID group (8) do not match (S110: NO), and in the condition processing of FIG. It is determined that the number of SSIDs received is zero (S203: YES), and in the second search process of FIG. 7, the number-of-times search process (S307) is executed. As a result, as shown in FIG. 11C, I34 and I35 are newly received and included in the third SSID group (8). Thereby, it is possible to suppress an SSID search omission for a mismatched channel in which there is a high possibility that there is an access point AP that is not searched in the first search process due to a temporary deterioration of the communication environment.

  According to the present embodiment, the unit search is executed twice, and the first identification information group acquired by the first unit search matches the second identification information group acquired by the second unit search. In this case, it is expected that the identification information of the connectable external communication device can be normally received. For this reason, such a matching channel is not subject to unit search in the second search step. On the other hand, if the first identification information group and the second identification information group do not match, connection is possible even if the unit search is repeated under the same search conditions because the communication environment is unstable. It is expected that the identification information of the external communication device cannot be received normally. For this reason, a unit search is executed with respect to such a mismatch channel under a search condition with higher accuracy than in the first search step. As a result, in the unit search of the second search step, it is possible to suppress the unit search from being continued in vain as much as the matching channel is excluded, and the first search is performed for the mismatched channel. Since the unit search is performed under a search condition with higher accuracy than the process, it is possible to suppress omission of search for identification information of connectable external communication devices.

  Further, the second search process is performed on the condition that the selection instruction for selecting the SSID displayed on the display unit 600 has not been received (S15: YES in FIG. 4). For this reason, it is possible to prevent the unit search from being performed wastefully even though the access point AP to be used for wireless communication has already been selected.

  FIG. 12 shows a control process according to another embodiment. In the second embodiment, the same configurations and processes as those of the first embodiment described above are denoted by the same reference numerals, and the description thereof is omitted.

  After completing the first search process (S11), the CPU 110 initializes a search end flag to zero (S701). If the search end flag is zero, it means that the second search process is executed, and if the search end flag is 1, it means that the second search process is stopped. When CPU 110 determines not to accept an SSID selection instruction (S13: NO), CPU 110 determines whether or not the search end flag is zero (S702).

  CPU110 performs a 2nd search process, when it is judged that a search end flag is zero (S702: YES) (S16). If the CPU 110 determines that a new SSID has been received as a result of executing the second search process (S17: YES), the CPU 110 can further receive a new SSID by executing the second search process again. High nature. Therefore, the CPU 110 proceeds to the processes of S18 and S12 while the search end flag remains zero. For this reason, the second search process can be executed again.

  On the other hand, if the CPU 110 determines that a new SSID has not been received as a result of executing the second search process (S17: NO), the CPU 110 may not be able to receive a new SSID even if the second search process is executed again. High nature. Therefore, the CPU 110 sets the search end flag to 1 (S703), and proceeds to the process of S12. Thereby, the second search process is stopped thereafter. For this reason, it is possible to prevent the unit search from being performed wastefully even though the situation in which a new SSID cannot be received continues.

  The identification information search method disclosed in this specification searches for identification information of an external communication device using a wireless communication unit that transmits and receives data by designating an arbitrary communication channel from among a plurality of communication channels. A method for retrieving identification information, wherein a request signal for requesting identification information of an unspecified number of external communication devices is transmitted once to the wireless communication unit, and the request signal is transmitted within a predetermined reception time from the time of transmission of the request signal. The unit search for acquiring the identification information of the external communication device received by the wireless communication unit as the identification information group is acquired by the first search step that is performed twice for each communication channel and the unit search for the first time. A first determination step for determining, for each communication channel, whether or not the first identification information group matches the second identification information group acquired by the second unit search; and the plurality of communication channels of The unit search is performed under a condition different from that of the first search step for each mismatch channel determined that the first identification information group and the second identification information group do not match in the first determination step. A second search step to be performed. According to this identification information search method, the unit search is executed twice, the first identification information group acquired by the first unit search, and the second identification information group acquired by the second unit search, If they match, it is expected that the identification information of the connectable external communication device has been successfully received. For this reason, such a matching channel is not subject to unit search in the second search step. On the other hand, if the first identification information group and the second identification information group do not match, connection is possible even if the unit search is repeated under the same search conditions because the communication environment is unstable. It is expected that the identification information of the external communication device cannot be received normally. For this reason, a unit search is executed for such a mismatched channel under a search condition different from that in the first search step. As a result, in the unit search of the second search step, it is possible to suppress the unit search from being continued in vain as much as the matching channel is excluded, and the first search is performed for the mismatched channel. Since the unit search is performed under a search condition different from the process, it is possible to suppress a search omission of identification information of connectable external communication devices.

  A wireless communication device disclosed in the present specification includes a wireless communication unit that transmits and receives data by designating an arbitrary communication channel from among a plurality of communication channels, a control unit, a storage unit, and a display unit. The control unit causes the wireless communication unit to transmit a request signal for requesting identification information of an unspecified number of external communication devices once, and transmits the request signal within a predetermined reception time from when the request signal is transmitted. The unit search for storing the identification information of the external communication device received by the unit in the storage unit as an identification information group is performed twice for each communication channel by the first search process and the first unit search. The first identification information group stored in the storage unit and the second identification information group stored in the storage unit by the second unit search are determined for each communication channel. 1 decision process and multiple Among the communication channels, for the matching channel determined to match the first identification information group and the second identification information group in the first determination process, the matching channel is stored in the storage unit as the matching channel. A first display process for displaying the identification name of the identification information included in the identification information group on the display unit, and the first identification information group and the 2 in the first determination process among the plurality of communication channels. A second search process for performing the unit search under a condition different from the first search process for each unmatched channel that is determined not to match the identification information group for the first time, and the second display process after the first display process. A second display process for displaying the identification name of the identification information included in the identification information group for each of the mismatched channels stored in the storage unit by the unit search in the search process on the display unit. According to the wireless communication device, in the unit search of the second search process, it is possible to suppress the unit search from being unnecessarily continued as much as the matching channel is excluded. Since unit search is performed under a search condition different from that of the first search process, it is possible to suppress omission of search for identification information of connectable external communication devices.

  In the wireless communication apparatus, the control unit may perform the unit search in the second search process by making the reception time longer than the first search process for each of the mismatch channels. According to the present wireless communication device, in the second search process, the unit search is performed for each inconsistent channel with a longer reception time than the unit search of the first search process, resulting in the length of the reception time of the identification information. The omission of retrieval of identification information can be suppressed.

  In the wireless communication apparatus, the control unit may perform the unit search three or more times for each mismatched channel in the second search process. According to this wireless communication apparatus, in the second search process, the unit search is repeated more frequently than the first search process for each unmatched channel. Therefore, it is possible to suppress omissions in the identification information due to the number of searches.

  In the wireless communication apparatus, the control unit may perform the unit search in the second search process by increasing the strength of the radio wave transmitted from the first search process for each of the mismatch channels. According to the wireless communication device, in the second search process, the unit search is performed by increasing the strength of the radio wave transmitted from the first search process for each unmatched channel. Search omission can be suppressed.

  In the wireless communication device, the control unit may include at least a number of identification information included in the first identification information group and a number of identification information included in the second identification information group for each of the mismatched channels. A second determination process is performed to determine whether the number of one identification information has reached the upper limit number of identification information that can be received within the reception time, and the second determination process is performed in the second search process. Then, the unit search may be performed by making the reception time longer than that of the first search process for the inconsistent channel for which it is determined that the number of the at least one identification information has reached the upper limit number. According to this wireless communication apparatus, the number of pieces of identification information included in the identification information group can be received within the reception time of one unit search of the first search process for one unit search in the first search process. When the upper limit number of identification information is reached, there is a high possibility that there is an external communication device that is not searched within the reception time. Therefore, according to this wireless communication device, at least one of the number of identification information included in the first identification information group and the number of identification information included in the second identification information group has reached the upper limit number. A unit search is performed for the unmatched channel by extending the first search processing reception time. Thereby, it is possible to suppress an omission of retrieval of identification information for a mismatch channel in which there is a high possibility that there is an external communication device that is not retrieved in the first retrieval process due to the length of reception time of identification information.

  In the wireless communication apparatus, for each of the mismatched channels, the control unit may select either the number of identification information included in the first identification information group or the number of identification information included in the second identification information group. A third determination process is performed to determine whether the number of identification information of one of them is zero. In the second search process, the number of identification information of any one of the third determination processes is zero. The unit search may be performed three or more times for the mismatched channel determined to be present. According to the wireless communication apparatus, when the number of pieces of identification information included in the identification information group is zero for one unit search in the first search process, the unit in the first search process is temporarily deteriorated due to temporary deterioration of the communication environment. It is likely that the search was not successful. Therefore, according to this wireless communication apparatus, it is determined that one of the number of identification information included in the first identification information group and the number of identification information included in the second identification information group is zero. The unit search is performed on the unmatched channel by increasing the number of repetitions compared to the first search process. Thereby, it is possible to suppress omission of retrieval of identification information for a mismatched channel in which there is a high possibility that there is an external communication device that is not searched due to temporary deterioration of the communication environment.

  In the wireless communication apparatus, the control unit may determine which of the number of identification information included in the first identification information group and the number of identification information included in the second identification information group in the second determination process. The number of identification information included in the first identification information group and the number of identification information included in the second identification information group are determined for each of the mismatched channels determined to have not reached the upper limit. A third determination process is performed to determine whether the number of any one piece of identification information is zero, and in the second search process, the number of any one piece of identification information is zero in the third determination process. The unit search is performed three or more times for each of the inconsistent channels determined to be the number of identification information included in the first identification information group in the third determination process, and the second identification information Identification information contained in the group To the Mismatch Channel both it is determined that the non-zero number of may be configured to perform the unit search strongly wave strength than the first search process. According to this wireless communication apparatus, the second search process can be performed with the search condition for each matching channel according to the cause of the mismatch.

  In the wireless communication device, further comprising an operation unit, the control unit, when the operation unit has not received a selection instruction to select the identification information displayed on the display unit by the first display processing, It is good also as a structure which does not perform a said 2nd search process, when the said 2nd search process is performed and the said operation part receives the said selection instruction | indication. According to the wireless communication device, the second search process is performed on the condition that the selection instruction for selecting the identification information displayed on the display unit has not been accepted. For this reason, it is possible to prevent the unit search from being performed wastefully even though the access point used for wireless communication has already been selected.

  In the wireless communication apparatus, the control unit, for each mismatched channel, the identification information group stored in the storage unit by execution of the second search process, and the above-described already before the execution of the second search process, If the identification information group stored in the storage unit does not match, the second search process may be executed again, and if they match, the second search process may be stopped. According to the wireless communication device, the second search process is performed again on condition that new identification information is stored in the storage unit by executing the second search process. For this reason, it is possible to prevent the unit search from being performed wastefully even though the situation where new identification information cannot be acquired continues.

  The technology disclosed in the present specification is not limited to the above-described embodiment, and can be modified into various forms without departing from the gist thereof. For example, the following modifications are possible.

  In the above embodiment, the printer 10 is exemplified as the wireless communication device. However, the wireless communication device is not limited to this, and an image forming device that forms an image, a reading device that reads a document, a printing function, a reading function, and the like. It may be a copier or multifunction machine having the above functions. The wireless communication device is not limited to one having an image forming function, and may be a server, a personal computer, a communication terminal such as a smartphone or a tablet, or the like.

  In the above embodiment, the control unit 100 configured by an ASIC having one CPU is illustrated as the control unit. However, the control unit is not limited to this, and includes one or a plurality of CPUs, a CPU and an AISC. It may be configured with only a hardware circuit such as a hardware circuit such as the above.

  In the above embodiment, the RAM 400 is exemplified as the storage unit. However, the storage unit is not limited to this, and a rewritable nonvolatile memory such as NVRAM, flash memory, HDD, or EEPROM may be used.

  In the above embodiment, the wireless communication interface 200 capable of executing both the infrastructure mode and the ad hoc mode is illustrated as the wireless communication unit. However, the wireless communication unit is not limited to this, and the infrastructure mode and the ad hoc mode Either one of the above may be executable.

  In the above embodiment, the SSID is exemplified as the identification information. However, the identification information is not limited to this, and may be information that can identify the external communication device.

  In the SSID search process of FIG. 4, if the CPU 110 determines not to accept an SSID selection instruction (S13: NO), the CPU 110 always executes the second search process regardless of whether or not the selection instruction is accepted. May be. Further, the CPU 110 may always execute the second search process after executing the process of S12 regardless of whether or not an SSID selection instruction is accepted.

  In the second search process of FIG. 7, the CPU 110 selects one or two of the time-up search process (S305), the number-of-times search process (S307), and the transmission strength increase search process (S308) for the mismatched channels. You may only do it.

  10: printer 100: control unit 200: wireless communication interface 400: RAM 500: operation unit 600: display unit AP: access point W: external wireless device

Claims (9)

An identification information search method for searching for identification information of an external communication device using a wireless communication unit that transmits and receives data by designating an arbitrary communication channel from a plurality of communication channels,
Identification information of the external communication device that causes the wireless communication unit to transmit a request signal for requesting identification information of the external communication device once and received by the wireless communication unit within a predetermined reception time from the time of transmission of the request signal. A first search step of performing a unit search for acquiring the ID as an identification information group twice for each communication channel;
A first determination is made for each communication channel whether or not the first identification information group acquired by the first unit search matches the second identification information group acquired by the second unit search. 1 judgment process;
Among the plurality of communication channels, a condition different from that in the first search step is determined for each non-matching channel in which the first identification information group and the second identification information group are determined not to match in the first determination step. look including a second search step of performing the unit search under,
When the identification information group acquired by executing the second search step does not match the identification information group already acquired before the execution of the second search step for each mismatched channel, the second search step The method for searching for identification information is executed again, and if the two match, the second search step is stopped . A wireless communication unit that transmits and receives data by designating an arbitrary communication channel from among a plurality of communication channels;
A control unit;
A storage unit;
A display unit;
An operation unit;
With
The controller is
Identification information of the external communication device that causes the wireless communication unit to transmit a request signal for requesting identification information of the external communication device once and received by the wireless communication unit within a predetermined reception time from the time of transmission of the request signal. A first search process in which the unit search is stored twice in the storage unit as an identification information group for each communication channel;
Whether or not the first identification information group stored in the storage unit by the first unit search matches the second identification information group stored in the storage unit by the second unit search. A first determination process for determining each communication channel;
Among the plurality of communication channels, for the matching channel that is determined to match the first identification information group and the second identification information group in the first determination process, the matching channel is stored in the storage unit. A first display process for displaying an identification name of identification information included in the stored identification information group on the display unit;
Conditions different from those in the first search process for each non-matching channel in which the first identification information group and the second identification information group are determined not to match in the first determination process among the plurality of communication channels. A second search process for performing the unit search under
After the first display process, a second display for causing the display unit to display the identification name of the identification information included in the identification information group for each of the mismatched channels stored in the storage unit by the unit search in the second search process processing and, to run,
When the operation unit does not receive a selection instruction for selecting the identification information displayed on the display unit by the first display process, the second search process is executed, and the operation unit receives the selection instruction. A wireless communication device that does not execute the second search process .   A wireless communication unit that transmits and receives data by designating an arbitrary communication channel from among a plurality of communication channels;
  A control unit;
  A storage unit;
  A display unit;
  With
  The controller is
    Identification information of the external communication device that causes the wireless communication unit to transmit a request signal for requesting identification information of the external communication device once and received by the wireless communication unit within a predetermined reception time from the time of transmission of the request signal. A first search process in which the unit search is stored twice in the storage unit as an identification information group for each communication channel;
    Whether or not the first identification information group stored in the storage unit by the first unit search matches the second identification information group stored in the storage unit by the second unit search. A first determination process for determining each communication channel;
    Among the plurality of communication channels, for the matching channel that is determined to match the first identification information group and the second identification information group in the first determination process, the matching channel is stored in the storage unit. A first display process for displaying an identification name of identification information included in the stored identification information group on the display unit;
    Conditions different from those in the first search process for each non-matching channel in which the first identification information group and the second identification information group are determined not to match in the first determination process among the plurality of communication channels. A second search process for performing the unit search under
    After the first display process, a second display for causing the display unit to display the identification name of the identification information included in the identification information group for each of the mismatched channels stored in the storage unit by the unit search in the second search process Process, and
  The controller is
    For each non-matching channel, the identification information group stored in the storage unit by the execution of the second search process matches the identification information group already stored in the storage unit before the execution of the second search process. If not, the wireless communication device executes the second search process again, and stops the second search process if they match. The wireless communication apparatus according to claim 2 or 3 ,
The controller is
In the second search process, a wireless communication apparatus that performs the unit search for each of the mismatched channels with a longer reception time than the first search process. The wireless communication apparatus according to claim 2 or 3 ,
The controller is
In the second search process, a wireless communication apparatus that performs the unit search three or more times for each mismatched channel. The wireless communication apparatus according to claim 2 or 3 ,
The controller is
In the second search process, the wireless communication apparatus performs the unit search for each mismatched channel by increasing the intensity of a radio wave to be transmitted compared to the first search process. The wireless communication apparatus according to claim 4 , wherein
The controller is
For each non-matching channel, the number of pieces of identification information included in the first identification information group and the number of pieces of identification information included in the second identification information group is the reception time. A second determination process is performed to determine whether or not the upper limit number of identification information that can be received is reached,
In the second search process, the reception time is made longer than the first search process for the unmatched channel for which the number of the at least one identification information is determined to have reached the upper limit number in the second determination process. And performing the unit search. The wireless communication device according to claim 5 , wherein
The controller is
For each non-matching channel, the number of identification information included in the first identification information group and the number of identification information included in the second identification information group is zero. Execute a third determination process for determining whether or not
In the second search process, a wireless communication apparatus that performs the unit search three or more times for the non-matching channel for which the number of identification information of any one of the third determination processes is determined to be zero. The wireless communication device according to claim 7 , wherein
The controller is
In the second determination process, it is determined that neither the number of identification information included in the first identification information group nor the number of identification information included in the second identification information group has reached the upper limit. For each of the mismatched channels, the number of identification information included in the first identification information group and the number of identification information included in the second identification information group is zero. Execute a third determination process for determining whether or not there is,
In the second search process,
The unit search is performed three or more times for each of the mismatched channels determined that the number of the identification information of any one of the third determination process is zero,
It is determined that the number of identification information included in the first identification information group and the number of identification information included in the second identification information group are not zero in the third determination process. On the other hand, the wireless communication apparatus performs the unit search by increasing the intensity of the radio wave to be transmitted from the first search process.

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